The exception was polesitter Kyle Busch, who led 190 of 200 laps in registering a dominating victory at Phoenix International Raceway, his eighth in 19 starts at the track.

In a race that saw defending series champion and seventh-place finisher Chase Elliott trim Xfinityleader Chris Buescher's margin in the standings from 24 to 18 points, Busch ran away with the event, crossing the finish line 3.097 seconds ahead of runner-up Brad Keselowski.

After winning his 47th pole earlier in the day (extending his series record), Busch picked up his 76th Xfinityvictory (extending his series record). The driver of the No. 54 Joe Gibbs Racing Toyota now has led 1,636 laps at PIR, second most at any track behind Bristol (1,768).

The win was Busch's fifth from the pole at PIR.

"It wasn't particularly hard, obviously," Busch said about the ease of his victory. "I do remember that there was one other time here I think I led 200 of 200 (laps)... We've done that here before. Today was close. We just weren't able to get good enough pit stops to come out of the pits with the lead each time and hold the lead that we had.

"But, all in all, it was a very fast racecar — flawless, really."

Keselowski's No. 22 Team Penske Ford was fast but not in Busch's class.

"We had a great effort," Keselowski said. "We had a great day on pit road. The guys on the pit crew did a great job there. We gained spots, so that was really cool and real fun, but we just needed a lot more speed to run with the 54. Either way, it was a pretty solid day."

JGR drivers Erik Jones and Daniel Suarez ran third and fourth, respectively, giving the organization three of the top four finishing positions. Ty Dillon came home fifth, followed by Regan Smith.

Buescher finished 13th, one lap down, and lost a fourth of his points lead over the reigning champion. But he can clinch the series title with a finish of 13th or better next Saturday at Homestead-Miami Speedway.

"In the grand scheme of things, we need to go to Homestead and we need to have a good day and do what we did there last year – just run around and stay out of trouble," Buescher said. "Run fifth – that would be just fine.

"When you look at the averages and points gained versus our needed position to finish, our window is getting bigger as we go through these last four races, so that makes me feel good as we go to Homestead. Even though they gained some points, honestly, unless something crazy happens at Homestead it's just not going be enough."

Busch, on the other hand, is in a dogfight for one of three available spots in the Chase for the NASCAR Sprint Cup Championship Round next week at Homestead. But first he'll have to survive Sunday's Quicken Loans Race for Heroes 500 at PIR (2:30 p.m. ET on NBC).

"We got our M&M's Camry a little bit better there in Happy Hour," Busch said of Saturday's final Sprint Cup practice session. "It was good. I'd like it to be better than it was, but we'll see how it stacks up in the race. I learned some things here today that will help me, and I'm looking forward to it."

Busch, who is second on the Chase Grid, will start 10th in Sunday's race.